Amazon’s famous “1-Click Ordering System” patent has competition. And it could be old enough to scupper its suit against Barnes & Noble.

Silicon Valley-based OpenTV, which makes middleware for set-top boxes to enable interactive TV, claims it thought of “one interaction shopping” back in April 1994 – and has the patent to prove it.

And with just nine days to go before the two-year deadline for broadening the patent, the company is trying to make it absolutely clear that it includes “single interaction ‘one click’ shopping and set-top box storage of personal information to facilitate television commerce.”

“Filling in name, address and credit card details with a TV remote control is much harder than with a keyboard,” explained Craig P. Opperman, OpenTV’s recently appointed chief intellectual property officer. “That’s why this is so important to us.”

Opperman said the company is seeking only to protect its customers – cable TV companies such as EchoStar’s DISH Network and the UK’s BSkyB – from the same fate at the hands of Amazon as Barnes & Noble.com.

The online arm of the bookstore chain is currently fighting Amazon.com in federal appeals court to lift the preliminary injunction barring Barnes & Noble.com from using single-click online purchasing. The injunction has been in place since last December. Both sides see it as crucial to their holiday shopping efforts.

“Amazon could be precluded from using its patent against anyone practicing what is taught (described) in our patent,” said Opperman.

But he also hinted things could get ugly once the patent is awarded to OpenTV. “Then it would become valuable intellectual property, and it may be appropriate to use it against our competitors.”

A spokesman for Barnes & Noble.com said the company could not comment while the Amazon case was in litigation.

The World’s Most Indebted Bookstore issued a statement saying OpenTV’s system just applies to TV commerce, while its system is for people using the Web.

“The technology in OpenTV’s patent depends upon use of a proprietary continuous repetitive transmission of data and computer code to the purchasers’ computer or television set-top box,” it read.

But OpenTV’s lawyers are going after the entire “client-server” relationship – which could conceivably cover couch potatoes and QVC addicts.

Jesse Jenner, an intellectual property attorney at Fish & Neave in New York, said that OpenTV’s claim to prior art depended entirely on who filed what when. “If any of their claims overlap, it could mean trouble for Amazon.”